1. The Field of the Invention
The present invention generally relates to the field of light curing devices and, more specifically, to light curing dental devices and methods for irradiating and curing photosensitive dental filling compounds.
2. The Relevant Technology
In the field of dentistry, dental cavities are often filled and/or sealed with photosensitive compounds that are cured by exposure to radiant energy, such as visible light. These compounds, commonly referred to as light-curable compounds, are placed within dental cavity preparations or onto dental surfaces where they are subsequently irradiated by light. The radiated light causes photosensitive components within the compounds to polymerize, thereby hardening the light-curable compounds within the dental cavity preparation or another desired location.
Light is typically directed to the light-curable compounds by a light-generating dental device comprising a lamp, such as a halogen lamp bulb, and a light guide, such as a fiber optic wand that can capture some of the light that is generated by the lamp. Special reflectors and filters are typically employed to control the quantity and wavelength of light that is permitted to enter the fiber optic wand. Light traveling through the fiber optic wand is finally dispersed out of a tip at a desired location within a patient's mouth.
One problem with existing LED light-generating devices, as well as with other light-generating devices which incorporate lamps, is they require a fiber optic wand to carry the light emitted by the lamp from within the light-generating device to the application site where the light is finally directed to a desired location. Light-generating devices may be manufactured with integrated fiber optic wands or sold with separate and detachable fiber optic wands. Although fiber optic wands are useful for their intended purposes, they are undesirable because they add to the cost of equipment, and hence to the total cost for performing dental procedures with light-curable compounds
Another problem with existing light-generating devices is that they are not very efficient. In particular, a large quantity of radiation energy is lost due to filtering, dissipated light, and light that is not reflected and properly channeled into the fiber optic wand. This is a problem because it generally results in increased power requirements for generating a desired output of radiation. Another problem is that complicated cooling systems are required to compensate for the heat that is generated by unchanneled and unused light, such as the light that is absorbed by special filters, reflective surfaces, and shields.
In an attempt to overcome these aforementioned problems, some light-generating devices have been manufactured with alternative light generating sources, such as light-emitting diodes (LEDs) which may be configured to radiate light at only desired wavelengths, thereby eliminating the need for special filters and generally reducing the amount of input power required to generate a desired output of radiation.
LEDs, however, emit light at a wide angle of dispersion, about 120°, which makes it difficult to focus the radiated light into the fiber optic wand. In order to capture the widely dispersed light, existing LED light-generating devices typically comprise special focusing reflectors and complicated designs that are required for housing the reflectors.
Yet another problem with existing devices is that they are not able to properly focus the light that is emitted from the LED or other light-generating source once it is directed out of the fiber optic wand. This is a problem because light emitted out of the fiber optic wand may create problems when it irradiates sensitive mouth tissues. Accordingly, it is desirable to focus the light only onto the light-curable compounds. Focusing the light onto the light-curable compounds can also be beneficial for reducing the duration of irradiation that is required to cure the light-curable compounds.
Accordingly, in view of the foregoing, there is currently a need in the art for improved devices for focusing light from light-generating sources for curing light-curable compounds during dental procedures.